Results 1 to 2 of 2

Math Help - Sample Mean

  1. #1
    Newbie
    Joined
    Jun 2009
    From
    Delaware
    Posts
    1

    Sample Mean

    I'm new to this site. I am a bit lost on this problem, could I request assistance? Thanks

    A coin-operated coffee machine made by BIG Corporation was designed to discharge a mean of eight ounces of coffee per cup. If it dispenses more that that on average, the corporation may lose money, and if it dispenses less, the customers may complain.
    BIG Corporation would like to estimate the mean amount of coffee, μ, dispensed per cup by this machine. BIG will choose a random sample of cup amounts dispensed by this machine and use this sample to estimate μ. Assuming that the standard deviation of cup amounts dispensed by this machine is 0.42ounces, what is the minimum sample size needed in order for BIG to be 90%confident that its estimate is within 0.08ounces of μ?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by SuZQ View Post
    I'm new to this site. I am a bit lost on this problem, could I request assistance? Thanks

    A coin-operated coffee machine made by BIG Corporation was designed to discharge a mean of eight ounces of coffee per cup. If it dispenses more that that on average, the corporation may lose money, and if it dispenses less, the customers may complain.
    BIG Corporation would like to estimate the mean amount of coffee, μ, dispensed per cup by this machine. BIG will choose a random sample of cup amounts dispensed by this machine and use this sample to estimate μ. Assuming that the standard deviation of cup amounts dispensed by this machine is 0.42ounces, what is the minimum sample size needed in order for BIG to be 90%confident that its estimate is within 0.08ounces of μ?
    Use the fact that if you were constructing a confidence interval then the endpoints would be \overline{x} \pm z_{\alpha /2} \frac{\sigma}{\sqrt{n}}.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. One sample t-test CLASHING with paired sample t-test?
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: February 15th 2011, 09:34 PM
  2. Sample distribution of sample variance
    Posted in the Statistics Forum
    Replies: 10
    Last Post: November 16th 2009, 12:12 PM
  3. variance of sample mean and sample standard deviation
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: July 24th 2009, 05:20 AM
  4. Replies: 2
    Last Post: May 29th 2009, 09:32 AM
  5. Sample Random Sample Question 2
    Posted in the Advanced Statistics Forum
    Replies: 2
    Last Post: January 7th 2008, 06:58 AM

Search Tags


/mathhelpforum @mathhelpforum